Temperature compensation optical fiber grating steel bar corrosion sensor and temperature compensation method thereof

Abstract

The invention provides a temperature compensation optical fiber grating steel bar corrosion sensor and a temperature compensation method thereof. The temperature compensation optical fiber grating steel bar corrosion sensor comprises a cantilever beam arranged in a case, optical fiber gratings and a probe. The cantilever beam is provided with a fixed end and a free end, wherein the fixed end is fixedly connected with the case; the probe is mounted on the free end; the optical fiber gratings are adhered to the cantilever beam; the case is provided with a steel bar contact unit and a suspension unit; the probe penetrates out of the suspension unit. The compensation method comprises sensing the central wavelength shift of the optical fiber grating caused by temperature change and steel bar corrosion through the two bare optical fiber gratings simultaneously; according to differences of the shift, achieving temperature compensation to steel bar corrosion measurement results and meanwhile obtaining the corrosion rate as well as the temperature change of the steel bars at a measured point. The temperature compensation method can greatly reduce the size of sensors based on the optical fiber grating sensing principles and improve the integration degree of the sensors. The temperature compensation optical fiber grating steel bar corrosion sensor has the advantages of being high in precision, small in size, good in duration, anti-electromagnetic and the like and can bring huge convenience to reinforced concrete structure testing.

Description

technical field [0001] The invention belongs to the technical fields of civil engineering and optical fiber sensing, and in particular relates to a temperature self-compensating optical fiber grating steel bar corrosion sensor and a temperature compensation method thereof. Background technique [0002] Reinforced concrete structures are widely used in sea-crossing bridges, ports and chemical plants. However, steel bars in reinforced concrete structures are prone to corrosion under the long-term action of corrosive media such as seawater and acid gas, which weakens the mechanical properties of steel bars and affects the bearing capacity of the entire reinforced concrete structure. Therefore, accurate measurement of steel corrosion in reinforced concrete structures is of great significance for evaluating the load-bearing performance of the entire reinforced concrete structure. Since the corrosion of steel bars is a long process, and the steel bars are embedded in the concrete...

AI Technical Summary

Problems solved by technology

It is difficult for these fiber grating corrosion sensors to ensure that the corrosion medium intrusion at the position of the corrosion sensitive element is consistent with the corrosion medium intrusion at the actual steel bar position, so the measurement results often cannot reflect the actual corrosion of the steel bar in the concrete

There are also sensors that use fiber gratings to directly measure the rust expansion of steel bars, but there are still disadvantages such as large disturbance to the corrosion environment of the measured steel bars, low measurement accuracy, small range and complex structure, which are difficult to apply in actual engineering

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